I guess you'd have to find a crash survivor to answer. I don't know if there are any operational guidelines for such an announcement, or if airlines prepare for announcing something they wish would not happen.
If in such a situation, I would suppose that all crew members would be totally focused on preventing a crash instead of making announcements.
If you hear the Lord's Prayer (or unprecedented cursing) coming over the intercom, I would count it as being informed.
Why do you ask?